Heretofore, there has been known an apparatus for heating a glass sheet by radiant heat rays from a heating source so as to form a predetermined temperature distribution (for example, refer to Patent Document 1). This apparatus has a heat-shielding plate disposed between a heating source and a glass sheet heated by the heating source so as to be substantially perpendicular to a surface of the glass sheet. This heat-shielding plate shields radiant heat rays that are incident obliquely to the surface of the glass sheet among the radiant heat rays from the heating source. Accordingly, by the above apparatus, it is possible to form a sharp temperature slope in a glass sheet, and to form a desired temperature distribution.
Patent Document 1: JP-A-2005-343747